The present invention relates generally to the field of electrochromic polymers, and in particular, to the use of commonly-available printing devices to create electrically sensitive color-changing displays.
Desktop printers have become common and ubiquitous computer peripherals. The range of technologies used for printing includes, for example, laser, ink jet, piezo electric jet, electrostatic jet, and continuous pressure jet printing processes. Ink-jet printers, for example, are generally popular because they offer high printing speed, low noise, easy color printing, simple construction and low price. The concepts and operational principles of ink jet printers, as well as the other technologies listed, are well known in the art. In general, a cartridge is detachably mounted on a carriage assembly which supports a printhead, and traverses the printhead across the width of a recording medium in a line recording operation along a guide shaft for printing an image or character on the recording medium.
An ink cartridge for such a printer is typically constructed as a unitary, detachable cartridge which includes a printhead comprising a plurality of nozzles in the form of a nozzle plate mounted on one end, and an ink container containing a reservoir of ink on the other. The cartridges generally additionally comprise drop generating structures and electrical connections adapted for electrically coupling the printhead to the printer which provide drop generating energy in response to information signals generated by the printer.
The manner of image generation varies from one technology to another. Certain types of printers generate a thermal pressure wave in the ink container and subsequently eject ink droplets from the ink container through a plurality of nozzles arranged vertically at a front end of the printhead provided with the cartridge. The thermal pressure wave is generated by selected heating elements installed in the nozzles, which heat the ink contained within the nozzles until the ink is ejected through an ejection orifice of the nozzles to produce a flying droplet of the ink. The droplet is deposited on the recording medium, forming a desired character and image.
Many printers incorporate a plurality of ink reservoirs, so as to facilitate the printing of more than one color. Additionally, many such printers incorporate a sufficient number of ink reservoirs to print in each of the three primary colors (red, yellow, and blue). By combining these colors, many such printers can print a continuous spectrum of colors so as to reproduce color images accurately.
Heretofore in the art, computer-controlled printing processes such as those described above have generally been used to produce static printed images. Although static printed images work well for many purposes, certain applications are more suited to the use of variable images. The liquid crystal display and cathode ray tube are two examples of variable image generation media. Each of the two types of media has inherent advantages and disadvantages. A static printed image has the advantage of being small, thin, and light, and therefore highly portable. It also retains its image without respect to whether electrical power is available. A variable image device has the advantage of displaying any arbitrary image at any point in time and of switching or modifying the colors and shapes of the image quickly, but is generally much larger and less portable than a sheet of paper, and requires electrical power to operate. What is needed in the art is a means of combining the portability and robustness of fixed image media with some of the image-variation characteristics of variable image media.
As noted, all of the prior technologies in the area of image presentation incorporate inherent disadvantages. The present invention overcomes these disadvantages through a combination of novel features. The following summary of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention, and is not intended to be a full description. A full appreciation of the various aspects of the invention can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
The present invention comprises a method of creating electrically modifiable images using a printer of the type described above. In one embodiment, one or more ink reservoirs of a printer cartridge are filled with an electrochromic ink. The printer thus prepared can be used to print electrochromic patterns on a surface using standard ink application methods. In certain embodiments, more than one ink reservoir is filled with electrochromic ink. In these embodiments, separate reservoirs are filled with separate ink formulations so that the characteristics of the electrochromic pattern can be varied.
In one embodiment, the present invention comprises a method for creating an electrochromic display comprising the steps of: printing a pattern in electrochromic ink on a first conductive surface and attaching a sheet having a conductive surface over the pattern such that the conductive surface of the sheet faces the first conductive surface.
In another embodiment, the present invention comprises a method for creating an electrochromic display comprising the steps of: printing a pattern in electrochromic ink on a first conductive surface on a first object; applying a metal oxide to a second conductive surface on a second object; applying an electrolyte to the metal oxide; and assembling the first and second objects with the electrolyte facing the electrochromic ink.
In yet another embodiment, the present invention comprises an electrochromic display device comprising: a conductive surface; an electrochromic pattern disposed on the conductive surface; and a conductor contacting at least some portion of the electrochromic pattern.
Another embodiment of the present invention comprises an electrochromic display device comprising: a first conductive surface; an electrochromic pattern disposed on the first conductive surface; an electrolyte layer disposed on the electrochromic pattern; a metal oxide layer disposed on the electrolyte layer; and a second conductive surface disposed on the metal oxide layer.
In another embodiment, the present invention comprises an apparatus for creating a customizable electrochromic display comprising: an ink reservoir containing electrochromic ink; a print head connected to the ink reservoir in such a manner as to receive electrochromic ink from the ink reservoir; a print media holding mechanism disposed in such a manner as to hold print media at the proper position for receiving electrochromic ink from the print head; and a print controller connected to the print head or print media holding mechanism in such a manner as to control the relative position of the print head and print media.
The novel features of the present invention will become apparent to those of skill in the art upon examination of the following detailed description of the invention or can be learned by practice of the present invention. It should be understood, however, that the detailed description of the invention and the specific examples presented, while indicating certain embodiments of the present invention, are provided for illustration purposes only because various changes and modifications within the spirit and scope of the invention will become apparent to those of skill in the art from the detailed description of the invention and claims that follow.